Effect of polystyrene addition on freeze casting of ceramic/camphene slurry for ultra-high porosity ceramics with aligned pore channels
Effect of polystyrene addition on freeze casting of ceramic/camphene slurry for ultra-high porosity ceramics with aligned pore channels
复制标题
DOI：
10.1111/j.1551-2916.2006.01311.x
复制
发表时间：
2006-12-01
影响因子：
3.9
通讯作者：
Kim, Hae-Won
中科院分区：
文献类型：
--
作者：
Koh, Young-Hag;Lee, Eun-Jung;Kim, Hae-Won
为制备具有定向孔道的超高孔率陶瓷，研究了聚苯乙烯(PS)的加入对初始固含量为5%的极稀氧化铝/榄烯浆料冻结行为的影响。为了实现这一点，在60℃下通过球磨制备了不同PS含量(相对于氧化铝粉末的10、20和30vol%)的浆料，然后在20℃的恒温下浇注到模具中，在去除冻结的榄烯后，对样品进行热处理以烧毁有机相并烧结氧化铝壁。PS粘结剂的加入显著提高了样品的生坯强度，使其能够轻松处理。所有烧结样品的超高孔率均为>；88%，孔结构没有坍塌，孔道完全相互连通。观察到具有不同孔隙结构的三个不同的带，即。外壳有细长的气孔，内区有长长的排列的孔道，中央有等轴孔。PS聚合物的含量对三个不同区域的孔形态有显著的影响。此外，还发现PS聚合物的加入对孔道的排列非常有利。
We investigated the effect of polystyrene (PS) addition on the freezing behavior of a very dilute alumina/camphene slurry with an initial solid loading of 5 vol% for the fabrication of ultra-high porosity ceramics with aligned pore channels. To accomplish this, slurries with various PS contents (10, 20, and 30 vol% in relation to the alumina powders) were prepared by ball milling at 60 degrees C and then cast into molds at a constant temperature of 20 degrees C. After removing the frozen camphene, the samples were heat treated to burn out the organic phases and sinter the alumina walls. The addition of the PS binder remarkably enhanced the green strength of the sample, making it possible to handle it without difficulty. All of the sintered samples showed ultra-high porosities of > 88% without the collapse of the porous structure, wherein the pore channels were completely interconnected. Three distinctive zones having different pore structures were observed, viz. the outer shell with elongated pores, the inner zone with long aligned pore channels, and the center with equiaxed pores. The content of the PS polymer significantly affected the pore morphologies in the three distinctive zones. In addition, it was found that the addition of the PS polymer was highly beneficial to the alignment of the pore channels.